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Sashnee Moodley:
The De Beers Group of Companies’ innovation division, De Beers Technologies South Africa (DebTech SA), has developed a novel density measurement system that can provide process plants with fast and accurate data on the material density profiles of particle samples. Mia Breytenbach tells us more.

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Mia Breytenbach: The RhoVol densimetric measurement system has been in development for several years and has now been made commercially available.
(B-roll- of the system, De Beers Logo, the offices, outside footage/B-roll, 0046E9, 00658O, 0050II)
De Beers Technologies South Africa research and development manager Dr Grant High tells us more.

DebTech research and development manager Dr Grant High:

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About three years ago, the idea of using some of De beers proprietary technology to measure volumes and coupled that with a rapid weight measurement came to the surface and the RhoVol was born.

The system has been in development for about three years, and the two machines we have on offer now we will be releasing to the market

The RhoVol densimetric profiling system is an instrument that measures the density profile of an ore sample, doesn’t matter what ore it is that you put as a sample into the machine.

The machine autonomously measures the weight and volume of each particle and then results in a density profile of your sample.

Mia Breytenbach: High explains the importance of the densimetric profiling process.

DebTech research and development manager Dr Grant High:

In any density separation process, it is important to know and understand the feed material, the density profile of the feed material, and the products,

And in the diamond industry we use density separation to separate our diamonds,

So to enhance the control of the systems, we developed the instrument to generate the density profiles.

Mia Breytenbach: High further highlights the advantages of the system.

DebTech research and development manager Dr Grant High:

The advantages of the Rhovol is accurate, timeous information on the density profiles of the material. Historically if you did density profile measurements it would typically mean taking samples and sending them off to a lab and you would get the information only in possibly in two or three weeks. And by that time, you can’t really do anything to improve your process.

The key feature of the machine is producing accurate density profile within about an hour, that enables plant metallurgists to then make changes to the plant to optimize their process. So the key advantage is accurate, timeous information.

Mia Breytenbach: In the RhoVol, De Beers Technologies has combined its vision size frequency distribution technique – which is a camera-based system for measuring the size of particles – with a rapid weight measurement device.

This allows for the mass and the volume to be determined with significant accuracy and speed. Data is also provided in real time, from which the density of each particle can be calculated.

The system’s software creates a three-dimensional (3D) model of each particle, so that any physical dimensions or ratios can be derived.

High explains that information about the shape of the particle – such as elongation, flatness and compactness – can be valuable in understanding the particular behaviour of a metallurgical process.

Processing plants can also use the RhoVol to audit the density profile of the run-of-mine material entering the plant, as well as material on the output side.

Through this, more effective monitoring of plant performance can be facilitated.

Mia Breytenbach: The RhoVol has an optional sorting functionality and can even raise the resolution of the 3D models by accommodating multiple passes of material through the system. By matching and merging images of the same particle, a high-fidelity 3D model can be generated, High explains.

The system can be applied across a range of commodities, as any mineral or material can be measured for its volume and mass. High notes that the density measurement range is not restricted and can be programmed to suit the product.

Since the RhoVol’s development, about eight systems have been deployed in the South African iron-ore industry. One system is also currently operational at a diamond mine in Botswana.
DebTech retains two systems for densimetric profiling of samples sent from universities and other tertiary education institutions.

Key advantages of the RhoVol includes the ability of a process rate of about 1 000 particles an hour, which is generally sufficient for a representative sample.

The advantages of the measurement system include high levels of repeatability.
Data is displayed live as it is captured and made available in a standard spreadsheet format on a per-particle basis.

Notably, no consumables are required in the testing process and no toxic liquids are involved in the testing, as in some sink float processes.
Critical components of the system are 3D-printed locally.

Mia Breytenbach: In addition to large miners using the system, smaller laboratories have also expressed interest in the system.

DebTech research and development manager Dr Grant High:

They are being applied in the diamond industry and in the iron-ore industry, there has been reasonable take up of the instrumentation.

High further highlights the impact the system can have on the mining industry.

DebTech research and development manager Dr Grant High:

The uptake in the iron-ore industry has indicated that there is a big impact on their systems they are able to timeously measure the density profile and make interventions on the plants which is directly coupled to their bottom line, to the quality of their sort and the grade of the material which they can sell on.

Mia Breytenbach: The RhoVol system is currently available in two sizes to accommodate coarse and fines-size fractions – one for material sized 3 mm to 8 mm, and a larger machine for material sized 8 mm to 25 mm.

However, De Beers Technologies has future plans for the systems.

High explains.

DebTech research and development manager Dr Grant High:

We are looking at developing an instrument to measure from 1 mm to 3 mm, so a very fine fraction, and also to add additional sensor measurements to the system, for example, adding a magnetic susceptibility measurement to the system, so then you will get both your density and particle information, such as shape, elongation or compactness, with the Rhovol as it is, but adding things to the machine like magnetic susceptibility.

Sashnee Moodley:
That’s Creamer Media’s Real Economy Report. Join us again next week for more news and insight into South Africa’s real economy.